1. Field of the Invention
The present invention relates to method and apparatus for image processing, which can achieve image processing adaptable to an image output device with respect to an output object image containing image data having several attributes in one image output (one page), for example, display, storage and printout, with high reproduction regardless of attributes of individual image data.
2. Description of the Related Art
JPN. PAT. APPLN. KOKAI Publication No. 11-215272 discloses the following technique in a digital multi-function printer. According to the technique, header information is added to each image data of the following image processings. One is image processing of a scanner input image captured by a scanner for copy and expansion to image memory. Another is image processing of a fax image (received using a facsimile function) and expansion to image memory. Another is image processing of an image having a print instruction (printout) from a host computer and expansion to image memory.
The foregoing Publication has the following description. According to the description, header information is added to each (mutually different) image data, and thereby, even if image data is concurrently input, processing is effectively performed, and the device configuration is simplified.
There have been known apparatus and method for image processing, which are able to handle different image data such as copy, fax and printer disclosed in the foregoing Publication. According to the image processing, in an image processing circuit, proper image processing is subjected to each of different image data in accordance with the kind of image data. The image data is converted into a single image format, and thereafter, stored in individual image data areas of an image memory. Then, the content stored in the image memory is output to a printer unit.
However, the foregoing apparatus and method for image processing disclosed in the Publication has the following problem. That is, the kind of the initial image of the image data stored in the image memory is not reflected (i.e., image data is stored in the single image format in the image memory, but the kind of the initial image is not classified).
Different kinds of images are allocated and/or edited to the same page area of the image memory using the processing configuration disclosed in the foregoing Publication. In this case, image data must be handled as multi-level data to improve image quality (to preferentially consider image quality, that is, realize high image quality). Moreover, non-compression image data outputable directly to a printer unit is required as a common image format. However, it is a matter of course that the image memory capacity required for editing image data per unit page becomes huge. As a result, the apparatus becomes large scale; therefore, the cost increases.
On the other hand, if the image is compressed to reduce the image memory capacity, there is a need of using a common format in the image memory. For this reason, it is difficult to employ different compression methods suitable to image characteristics of copy and printer; therefore, the compression method must be unified into one of those. Unless a compression method suitable to any one of those is used, a compression method common to each attribute of image data is employed as a compromise proposal. By doing so, the image memory capacity is reduced, but there is a problem that the image quality is reduced. In this case, since coding conversion is required, a processing mechanism for coding conversion must be newly added. As a result, the apparatus becomes large scale; therefore, the cost increases.